I have had similar problems with everything from the "Canon squeal" on my Canon A1 & AE-1P, slow shutter on my Mamiya TLR lens, Retina IIIc shutter, Minolta SRT mirror return problem etc... So, several years ago I was going to send my Mamiya C330S lens off for a CLA and I had just also just finished giving a noisy volume control my old (1973) Fender Twin Reverb guitar amp( I'm a guitar picker). I have always used the Deoxit Fader F5 for my amplifier potentiometers. This product has a long (replaceable) nozzle/tube and has an adjustable spray "L", "M", "H", anyway I had a thought about my old 65mm TLR lens and wondered if it would work on the shutter mechanism, well it has been several years and the the lens is still functioning as it should...I used to get this made in USA product at Radio Shack, and the last can I bought I believe was purchased through Amazon about $15...Good product...https://caig.com/deoxit-d-series/, their part # F5S-H6, it works for me...